Brake system for hoisting drums



March 15, 1960 J. H. WILSON 2,928,505 Y BRAKE SYSTEM FOR HOISTING DRUMSFiled NOV. 27, 1956 5 Sheets-Sheet l INVENTOR. John Hou Wilson H/SAGENT.

March 15, 1960 J. H. WILSON 2,928,505

BRAKE SYSTEM FOR HOISTING DRUMS Filed Nov. 27, 1956 5 Sheets-Sheet 2 wanIII/111111111!!! 'IIIII'IIIII; I

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569. INVENTOR. Jo hn Hard Wilson F15 flGENT.

March 15, 1960 J. H. WILSON BRAKE SYSTEM FOR HOISTING DRUMS 5Sheets-Sheet 3 Filed Nov. 27, 1956 HIS AGENT.

March 15, 1960 J. H. WILSON I BRAKE SYSTEM FOR HOISTING DRUMS 5Sheets-Sheet 4 Filed Nov. 27, 1956 INVENTOR. John Harc Wilson BY H15AGENT March 15, 1960 J. H. WILSON BRAKE SYSTEMVFOR HOISTING DRUMS 5Sheets-Sheet 5 Filed Nov. 27, 1956 T n mm. m. mm M M A WW a H R m% JUnite-d Sims. P tehtC 2,928,505 BRAKE SYSTEMFORZHOISTING DRUMS John HartWilson, Wichita Falls, Tex.

. -Applieation November 27', 1956, Serial No.. 624,608 4 Claims. Cl.188-77) This invention relates to. improvements inbrak'e systems andmore particularly to a brake system for hoistingdrums such as usedon'd'rillings rigs, well servicing rigs, and the like.

Various brake systems'h'ave been proposed heretofore, but these, forthemost part,'failed to adequately equalize the brakes to compensate forwear on the friction elements of the brake, or for irregularities if oneof the friction elements and/or one brake ring wears faster than anotherbrake ring. v

.The present brake system equalizes the pull on both brake bands onthehoisting drum of a drilling rig or the like, and furtherv equalizes aneven pull -on theen'tire width of each' brake band, ,as well ascompensating. automatically for the wear on the brake'bands.

I An. Object ,Ofthisinven'tion is to provide a brake band equalizerwhich will equalize a pair of brake bands on a ICC Fig.5 is a sectionalview taken on the 1ine: 5. 5; ot

Fig. 1, looking in the directionindic'ated by thearrows; Fig, 6 is asectional view takenon the line -6-6.of Fig. 1, looking in the directionindicated by the arrows; .Fig. 7 is a sectional viewv taken on theiline7- 7 of Fig. 1, looking in the direction indicated bythe arrows;

Fig. 8 is a sectional view taken on the line 8e- 8. of Fig. 1, lookingin the direction indicated by the arrows;

Fig. 9 is an enlarged .central, longitudinalsectional view through ananti-kick, dflShrPOt .type:hydraulic retarder, with portions showninelevation;

Fig. 10 is an enlarged, fragmentary, elevationalview of a brake positionindicator; v n

Fig. 11 is a fragmentary, sec'tionalview taken on the line11-'-11 ofFig.3, lookingin the-direction indicated by the arrows;

Fig. 12 is a fragmentary, elevational view of a servoair valve mechanismconnected. to the handbrake lever and to the air cylinder to actuatethe-brake bands;

Fig. 13 is an enlarged fragmentary plan view of the servo-brakeactuating mechanism attached to the brake actuator shaft;

Fig. 14 is an endview'of themechanism shown in Fig. 13 with parts brokenaway and shownin section;

,Fig. 15 is a side elevational view ofthe mechanism shown in Fig. 13;

" Yet another object of the invention is to provide a brake systemwherein the return movement of .the brake lever is'retarded byahyd'raulic retarder, but which al- .lows unimpeded movement in'theopposite direction.

A'fu'r'ther object of the invention is to'provide a brakeequalizer'which, while equalizing the loadsbetween-th'e 'two brakebands, will avoid any bending strain on the eye bolts which connect thebrake bands of the equalizer, due to the tilting of the equalizer beam.A sti l. further object of this invention. is topr'ovide a brakeequalizer, which, while equalizing the load between the two brake bands,will avoid any bending strain on the eye bolts which connect the brakebands to the equalizer, due to wearon the blocks'on the fixed ends ofthe brake bands;

With these objects in mind and others which will become manifest as thedescription proceeds, reference is 'to be had to thea'ccompanying'drawings, in which like reference characters designatelike parts in the several views thereof, in which: v 'Fig. l is anelevationalVieWofa hoisting drum, show- .ing the brake equalizerinstalled thereon, withfportions broken away and other portions shown,in. section, to bring out the details of. construction;

Fig. 2 is a fragmentary side 'elevational view of ahois'ting drum,showing the brakingv system. thereon;

Fig. 3 is a sectional view taken on the line 3-3 of Fig: 1, .lookinginthe direction indicated by the arrows; Fig. 4 is a fragmentary sectionalview, taken on the line ofFig. '1.,. lookingqinthe direction indicatedby the arrows;

Fig. 16.is a sectionalview-through a conventional; form of airservo-valve, such. as shown .iniEigs. 12 .thr.ough 1 5; and.

'Fig. 17 isan end elevational view of the servo-valve mechanism, shownapart from the-device.

With more detailed referenceito thedrawing the- 1inmeral 1 designatesthe base ofa rotary drillingrig on which draw works or hoistingmechanism2 i's mounted. A shaft 4 is mounted upon theframe of the drawworks 2, so as to support drum 6. thereonfor rotation thereof about theaxis of shaft 4. Thedrum 6 may beedriven by a power unit, in anyofseveral well known, conventional methods, for rotating the-drum so. asto wind cable thereonto, and. to permit unspooling of..the. cabletherefrom.

The frame of the draw works 2 hasa sub-,frame 8 secured thereto, whichsub frame extends substantially.

normalv to the axis. of the drum 6. Bearings 1.0 ..ar'e mounted onsub-frame 8,. on:the.1ower side thereof,.and are secured thereto bymeans of bolts 12. The bear,- ings 10 pivot on axial shaftw14,,whichshaft-.is ..secured toa beam member 16 immediately forwardofthe brake Vflanges 6a of drum 6. The beam "members 16 has vertical aperturespassingstherethrough, through...the central aperture of which a centralbolt 18 passes, andnside bolts 20 pass through the apertures neareach...end-thereof. The bolts 18 and'Ztlv extend upward and pass throughvertical. apertures formed in asecondfbeamf22. The bolt -18 has a nut 19on each end thereofto enable the adjusting of the beam 16 relative tothe beam ZZ. ,It is preferable to have the lower ofthe nuts '19jpinnedkeyed, as by a cotter key, to .preventrelative rotation thereof withrespect to .bolt,18

Wrench 19a is rovided'for.the,.nuts.19,.whicli wrench 19a islocked inplace. by, screwpin 19b passingihrough an aperture formed in the handle:thereof; It is preferable to have. theiapertures in one 'or"b'o'thof'the beams 16 and 'zz'looselyntting aroundthe respective bolts, so asto permit correct "alignmenriof the brake equalizer beam 22 withirespectto brakesi29. A spring 21 is telescoped over each of the bolts"20,"intermediate the beams 16. and22, so as tourgeth'erbeams apart. Nuts252a are provided at each. end of each bolt, 20,,so as to maintain bolts20 'in thecorrectrelatin with respect to beams 1'6 andj22. 1'Flie beamfurcated at each end, as will best be seen 'in'Fi 8,'the bifurcatedendsof which beam have transverse apertures 24 passing therethrough andthrough a swivel swivel 'block has apairof brake band sustaining anchor;:bolts' 28 attached thereto, which .bolts areadjustable by 7 means ofnuts. 30, so as to adjust eaph of the brake bands a block 26. The swivelblock 26 is positioned between .theears formed, by the bifurcated endsof bearn 2 2, which whenithe brakes are applied, without tending to bendthe eye bolts which connect to the respective fixed ends of the brakebands. ;-Also, it can be 'seen that when the brake blocks on therespective fixed'ends of the brake bands wear considerably, theequalizer beam 22 and the swivel beam 16'can swivel as a .unit, about"the shaft 14 in bearing 10, and about swivel 28a in the ends' of eyebolts 28, where they attach to the fixed ends of thebrakebands 29. Thesmall eye'bolt 2 911, the spring 29b and adjusting nut 29c move anextension of the eye bolt 28 to provide an adjustment of the in andoutposition of the respective fixed ends of the brake bands 29. v

The central bolt 18 has a spherical segment washer 32 thereon, beneaththe upper nut 19, to permitjlimited pivotal movement of beam 22'thereon, as will best be seen in Figs. 1 and 6. The bolts 28 securelyanchor brake bands 29, through blocks'26, to beam 22, whereupon, tensionis transmitted through bolt 18 to trans verse beam 16, which ispivotally mountedon' shaft 14 below subframe 8. The other end of each ofthe brake bands 29 is secured, by means of a clevis and eye-boltarrangement 34-36 to brake actuating levers 38, which levers, are inturn, secured to shaft 40.

Theshaft 40 may be rotated by actuation of brake lever 54, to manuallyapply brake bands 29, however,

to supplement or augment the application of the brake bands 29, afluidcylinder 4 6'is provided, which has a double acting plunger 44 therein,so upon application of fluid pressure to supply lines 46a or 4611, by asuitable valve, the plunger 44, which is connected to shaft 40 splinedto shaft 58a, which shaft 58a is mounted within bearings 60, as willbest be seen in Figs. 2, 3, and 11; Due to the reversal of drum 6, thebrake actuating lever 54 often has a tendency to kick or to rotate aboutpivotal member 62. However, an anti-kick, dash-pot type retarder 64 ispivotally connected to lever 52, which lever, through linkages 3436, isconnected to the brake bands 29 and to'the lever 54'by linkages 50 and56, whereby, upon rotation of shaft 40, the piston 70 forces fluid fromone end of cylinder 64 of the dash-pot retarder through a restrictingorifice 66 in check'valve 68 to the opposite end of the cylinder of thedash-pot retard er. However, upon the reverse movement of lever 54, thecheck valve 68 opens to'permit free flow of fluid to the opposite end ofthe cylinder 64. A fluid reservoir .72 maintains the cylinder 64 filledwith fluid at all times. An air bleeder 74 is provided to bleed air fromthe hydraulic system,

' as will best be seen in Fig. 9.

A needle valve 66a is provided for'valve 68 to regulate the flow offluid through orifice 66 from one side of the check valve member to theother side thereof.

A tension spring 76 is connected to the frame of the draw works Zand toa lever 78 on brake lever 54, so as through lever42, will rotate shaft40 in such degree as may be desired, since the valve may either be handoperated, foot'operated, or servo-mechanism operated.

The levers 38jare of such length,'-and are connected to' the respectiveclevises 34 in such manner as to exert a toggle action'on the'clevis,upon application of the brake, by fluid cylinder 44 operating by fluidpressure 'in cylinder 46.

An indicating pointer 48, as will best be seen in Fig. 10, is connectedthrough a linkage arrangement to a lever 52, so upon application ofbrakes, as by actuating lever 54 the pointer indicates the variousstages of brake engagement. I V

A brake actuating lever 54 is pivotally mounted on shaft 62, whichleverhas'a shorter lever78 attached thereto and extending downward therefromto which is connected a linkage 56, on which adjustable clevises 56a aremounted. One clevis 56a is pivotally connected to lever 78 and the otherclevis 56a is mounted'on'brake actuator shaft 58a. A further lever 58bis mountedon shaft 58a and is connected through linkage 50 to lever 52which is secured to shaft 40. The other end 'of the lever 52 extendsupward and has a lever 38a'thereon,which is pivotally connected toclevis 34 to actuate oneof the brake bands 29. A further lever 38 issecured to the opposite end of shaft 40, to actuate the otherbrake band29, when the brake lever 54 is applied. A clevis 79 is" also attached tolever 52 to actuate the hydraulic retarder, as will be more fully setout hereinafter. Clcvises 56a.are provided on linkage 56 for adjustingthe relative position. of the brake lever 54, to give the best operatingheight thereof for the individual driller.

to urge the brake lever into release position. v

A cylinder is positioned in aligned relation with cylinder 64, whichcylinder 65 has a vent 65a therein, so that the piston rod 71, on whichpiston is mounted, may extend through an O-ring seal. gland 73 into thecylinder 65. In this manner, the piston 70 displaces an equal amount offluid on either the out stroke or the return stroke thereof. Thereforethe hydraulic fluid circulated through pipe 75 from one side of thepiston 70 to the other side thereof in cylinder 64, is equal at alltimes. In this manner, a closed hydraulic system may be had with a pipe75a and reservoir 72 so thatthe system may be maintained sealed at alltimes, with the additional hydraulic fluid compensating for any leakagearound O-ring seal glands 73 or 73a.

An accordiontype boot 77 is connected in dust tight relation around theend of the cylinder 64 and the clevis 79 on connecting rod 71.

M0dified form of invention I that the shaft58a will be rotated uponmovement ot lever 54. a

A shaft 48a is mounted on. and extends outward from shaft,58a and has anindicating pointer 48 thereon to indicate the disconnected position ofthe brake bands '29, the engaged position of the brake bands 29 andthefinal stop position thereof.

A lever 58b ismounted on and secured to shaft 581; and extends downwardand has a servo-valve mechanism 81 thereon, aswillbe best seen in Figs.12 and 14. The valve is of a conventional character, such as shown inFig. .16,,whereiri, as the lever 58b is moved, it actuate's the valvemechanisms therein to direct fluid under pres sure from the supply line.Since the, servo valve 81 is connected to'a linkage 82 which connectswith 1ever 40 a, air will be directed from the supply line 84 throughservo valve 81, and out through one ofthe air supply lines 46b or 46a,which lead to opposite ends of fluid actuating cylinder 46; Inthis'manner, as pressure is manually applied to lever 54 to moveservo-valve 81 and linkage '82 in either direction, fluid is suppliedtothe end of the cylinder'46 and pressure will be applied to the pistontherein tomove the plunger 44a in the desired direction and the air'thatis in the opposite end of the'cylinder will be discharged out throughthe other of the supply lines 86 or 88 from that through which the airis being directed into the cylinder 46.

In this manner, the lever 54 is manually connected in such way as torotate shaft 40, which is connected to the movable end of the brakebands 29 through clevises 34 and eye bolts 36. However, in addition tothe manual application, air may be. applied through servo-valvemechanism 81 to aid in the rotation of the shaft 411. The servo-valvemechanism is of conventional design and may be so set as to pass therequired amount of air at such pressure as required, into cylinder 46 soas to augment the manual pressure on lever 54, or, if desired, the valvemay be adjusted so that the lever 54 may be merely a valve actuatorlever.

Having thus described the invention, what is claimed is:

1. A brake system for a hoisting drum comprising; a frame, a drummounted on said frame for rotation about the axis of said drum, a brakering secured to each end of said drum, a pair of brake bands mounted onsaid frame, each of said brake bands being cooperatively engageable withthe respective brake rings, a first longitudinal beam, pivot means onsaid frame exterior of said brake rings pivotally mounting said firstlongitudinal beam for pivotal movement about a longitudinal axis thereofso said first longitudinal beam will be in substantially parallelrelation to the axis of said drum, a second longitudinal beam positioneda spaced distance above said first longitudinal beam andbeing'substantially parallel thereto and extending at least to thecenter of each of said brake rings, said first longitudinal beam andsaid second longitudinal beam each having a substantially verticalaperture formed therethrough medially of the length thereof, a centralanchor member which is of substantially smaller diameter than thediameter of said apertures, which anchor member is positioned throughsaid medial apertures of the respective beams, said anchor member havingmeans on each end thereof to'restrain said second longitudinal beamwithin a predetermined maximum pivotal movement with respect to saidfirst longitudinal beam yet permitting limited pivotal movement of saidsecond longitudinal beam relative to said central anchor member, aresilient support member posimeans connected to opposite ends of saidbrake bands from said anchor means to actuate said brake bands.

2. A brake system as defined in claim 1, wherein said secondlongitudinal beam has a swivel block mounted near each end thereof, andwherein said means anchoring an end of each brake band comprises a pairof bars, each of which bars is independently adjustable, secured near anend of each of said brake bands and to said respective swivel blocks.

3. A brake system as defined in claim 1; wherein said support memberscomprise springs to resiliently support said second longitudinal beamwith respect to'said first longitudinal beam.

4. A brake system as defined in claim 1; wherein said first and secondlongitudinal beams are apertured with vertical, axially alignedapertures, one of which apertures is spaced outward on each side of saidmedial apertures, and wherein said central anchor member comprises abolt; and wherein a bolt is provided through each pair of axiallyaligned apertures which are spaced outward from said central apertures,and a compression spring telescoped over each of said last mentionedbolts and positioned intermediate said first longitudinal beam and saidsecond longitudinal beam to hold said beams in normal spaced apartrelation.

References Cited in the file of this patent UNITED STATES PATENTS2,465,164 Maier et al. Mar. 22, 1949

